Complete genome sequences of two Chinese virulent avian coronavirus infectious bronchitis virus variants.

Avian coronavirus infectious bronchitis virus (IBV) is variable, which causes many serotypes. Here we reported the complete genome sequences of two virulent IBV variants from China, GX-YL5 and GX-YL9, belonging to different serotypes. Differences between GX-YL5 and GX-YL9 were found mainly in stem-loop structure I in the predicted RNA secondary structure of open reading frame (ORF) 1b and the S protein gene fusion region, which will help us understand the molecular evolutionary mechanism of IBV and the disconcordance between the genotypes and serotypes of coronavirus.